1. Field of the Invention
The present invention relates to boots, and more particularly, to boots used in the mining industry.
2. Description of the Prior Art
Boots used by minors are traditionally made of rubber and are heavily reinforced by hard rubber caps and ribs. An average pair of boots presently used in the mining industry weighs approximately 8 lbs.
Boots for underground mining are usually supplied in two types, that is, a first type of a relatively light rubber material having a hard rubber toe cap, and relatively form-fitting ankle and calf portions with the front of the boot partially laced from the top. The other type of boot includes a heavier rubber on canvas construction having a hard rubber toe cap and a hard rubber metatarsal guard as well as thick rubber ribs over the guard and the toe cap. The lighter boot is comfortable and of thin flexible rubber, but can be utilized only by supervisory personnel underground, engineers and surveyors, trolley and truck operators,and underground maintenance personnel. They are unsafe and impractical to wear on any mining job that requires heavy manual work. It is important that personnel doing such jobs, that is, so-called miners, wear boots which are built up to sustain heavy wear conditions, that is, working and walking on freshly broken rock, with each piece of rock presenting sharp angles. It is also important that sufficient protection be provided to protect the metatarsal portion of the foot as well as the toes. There is always a danger of tumbling rocks of varying sizes on heavy equipment landing on that portion of the boot.
However, to date, the classical miner's boot appears to be a remnant of the equipment used by armor-clad knights in the Middle Ages, giving ample protection to the foot but no flexibility of movement.
The mining boot referred to above and as somewhat illustrated in U.S. Pat. No. 1,717,127, J. Toole, 1929, includes a heavily armored toe and metatarsal guard portion made up of steel and rubber in a rigid foot portion. In other words, there is no flexibility between the toe guard and metatarsal guard portion of the boot. On the other hand, any normal footwear requires the greatest amount of flexibility at this very area because of the hinging action of the toes relative to the remainder of the foot, in a normal walking attitude.
There have been some suggested improvements in so-called rubber boots provided with toe guard and metatarsal guards. For instance U.S. Pat. No. 3,308,560, J. P. Jones 1967, describes a rubber boot having a metatarsal and instep guard integral with the outer sole of the boot and overlapping with the trailing edge of a box toe. Slight gaps are left between the laminated liner and outer to allow for shifting movement between the metatarsal guard portion and the box toe. However, although this patent recognizes the problem, it does little to solve it since the flexing of the metatarsal guard relative to the box toe would only enhance the delamination of the laminated layers between which the guard and box toe are located.